The present invention relates to bearings, and more particularly to rolling element bearings with a device for establishing preload.
Certain bearing assemblies, such as “double bearing” assemblies for supporting X-ray tube actuators, include two axially spaced apart bearings rotatably coupling a shaft with a housing. Often, these bearing assemblies include a spring or other means to axially bias the bearing outer ring generally toward the inner ring in order to establish a preload. In order to enable the axial displacement of the outer ring, the fit between the outer surface of the outer ring and the inner surface of the housing must permit at least a limited amount of sliding movement of the bearing outer ring.
However, at elevated operating temperatures, the housing and/or the bearing expands, which may eliminate the sliding fit of the outer ring within the housing. As such, the outer ring may become “stuck” and create excessive clearance within the bearing itself (i.e., insufficient preload or no preload) or generate an inward radial force on the bearing that could cause skidding or sliding of the rolling elements within the bearing raceways.